Morning news brief: Trump finally wears mask, COVID-19 cases reach 12.3 million and more

Trump visited Walter Reed National Military Medical Center, a military medical facility outside Washington. The purpose of the visit was to meet with wounded soldiers and frontline health-care workers.

The Global Times has reported that German researcher Adrian Zenz and a think tank -- Australian Strategic Policy Institute -- will be sued for spreading 'disinformation about China'.

The death toll increased by 5,286 in the past 24 hours, taking the global tally of deaths caused by the novel coronavirus to 556,335, the WHO said.